Electrical convenience outlet



Sept. 26, 1939. R. w. HAGGAR 2,174,442

ELECTRICAL CONVENIENCE OUTLET Filed May 23, 19:58 2 Sheets-Sheet 1 Sept. 26, 1939. R. w. HAGGAR ELECTRICAL CONVENIENCE OUTLET Filed May 23, 1938 2 Sheets-Sheet 2 CID I-rluantclt' a mmumw a Ht-turne- Patented Sept. 26, 1939 UNITED STATES PATENT OFFICE ELECTRICAL CONVENIENCE OUTLET Robert W: Haggar, Hamilton, Ontario, Canada Application May 23, 1938, Serial No. 209,428

a Claims. 01. 173-330) My invention relates -to improvements in electrical convenience outlets of the kind wherein a receptacle of insulating material having electrical contacts disposed in proximity to slots through 5 the receptacle and connected to electric current leads is enclosed in a box inserted into a building wall, room base or other required location and a detachable plug having spaced apart tongue contacts connected by leads to the lamp or appliance desired to be energized has such tongue contacts inserted through the slots in the receptacle into contact with the contacts therein and held in such position by friction, and an object of myinvention is to devise means for guiding the plug 5 to its proper position relatively to the receptacle so that the tongue contactsof the former may register with the slots in the latter and thus facilitate the insertion of the tongue contacts into such receptacle slots to readily make contact with the receptacle contacts instead of having to fumble about to locate the plug with respect to the receptacle as is the case with existing convenience outlets.

A further object is to devise means for locking the plug to the receptacle against accidental displacement therefrom. a

A still further object isito devise means wherein when the outlet is employed in a polarized direct current circuit, the positive or negative contact to of the .plug can only contact the receptacle contact of like polarity.

With the above and other objects in view which will hereinafter appear as myspeciilcation proceeds my invention consists, in its preferred ems; bodiments, of the constructions all as hereinafter more particularly described and illustrated in the accompanying drawings in which- Fig. 1 represents a front View of a double convenience outlet constructed according to my in- 40 vention, showing a plug inserted into the left hand receptacle and also showing the guiding means for the plug located on the face plate 01' the outlet, and the locking means being positioned partly on'the plug arid partly on the re-,

#5 ceptacle.

Fig. 2 is a side view of the plug and receptacle shown in Fig. 1,the face plate being shown in section, the full line position of the plug indicating the initial position it assumes when beto ing attached to the receptacle and the dotted line position illustrating its final position when electrical contact has been established between receptacle and plug.

Fig. 3 isa plan view of the construction illusji trated in Fig. 1.

Fig. 4 is a similar view to Fig. 1 only illustrating a modification in which the locking means is partly on the plug and partly on the face plate.

Fig. 5 is a side view of the construction illus- I trated in Fig. 4, the full and dotted line positions 6 of the plug being as in Fig. 2.

Fig. 6 is a similar view to Figs. 1 or 4 showing a modified form of guiding and locking means for the plug.

Figs. '7 and 8 are respectively side and plan 510 views of the construction illustrated in Fig. 6.

Fig. 9 is a front view of a further modified form of convenience outlet constructed according to my invention in which the receptacle and face plate are formed integrally and the plug guiding 115 and locking means is incorporatedv therein.

Fig. 10 is a cross-sectional view of the combined receptacle and face plate shown in Fig. 9.

Figs. 11 and 12 illustrate in front and side views an attachment to the orthodox plug for enabling it to be guided and locked to the outlet.

Figs. 13 and. 14 show a construction in side view and front view showing the adaptation of my invention to a socket screw plug; and I Figs. 15 and 16 represent elevational views F taken at right angles to each other of a modified construction of tongue contacts on the plug for employment with receptacles in which its slots are horizontal instead of vertical.

Like characters of reference indicate correspending parts in the different views of the drawiIiSS.

Referring to the construction illustrated in Figs. 1 to 3 the receptacle I has a forward boss 2 with a transverse slot 3 of semi-circular crosssection in the upper part thereof underlying the space between two ribs'W extending outwardly from the face plate 5 and directed rearwardly and towards each other from top to bottom to 'guide a transversely extending hook member 6 of cylin- "40 drical cross-section formed on the periphery of the plug 1 which is provided with tongue electrical contacts 8, which in this case are preferably arcuate in shape (instead of being straight as is orthodox practice), and are insertable into the slots 9in the face of the receptacle 1 so as to make contact with the electrical contacts (not shown) therein in the usual manner.

' Where the slots 9 are disposed horizontally instead of vertically the tongue contacts 8 may be of the form illustrated in Figs. 15 and 16.

In order to apply the plug I to the receptacle l the hook member 6 of the former is inserted between the guide ribs 4 as illustrated in fulllines in Fig. 2 and pressed down until such hook mem- -.li5

Where the convenience outlet islocated on a wall higher than the appliance being used, the cross-slot 3 in the receptacle boss would be at the top as illustrated in Figs. 1 to 3 but when the outlet is in a base board or in any location below the appliance, then the receptacle would be reversed so that the cross-slot 3 is lowermost and the ribs 4 correspondingly located.

When the plug 1 is in the position illustrated in dotted lines in Fig. 2, it is locked to the receptacle l by the hook member 6 and will not become displaced accidentally. Any strain on the wires between plug and appliance will only tend to hold the plug more securely to the receptacle.

In order to remove the plug 1 from the receptacle I it is only necessary to swing up the former, for instance by means of the wire cord attached thereto, until it assumes the full line position of Fig. 2 and then pull it vertically a further extent when the hook member 6 will slide up the guide ribs 4 and become detached therefrom.

If the position of the cross-slot 3 is lowermost as suggested above to free the plug it would be swung downward instead of upward, in which case the whole outlet assembly would be merely reversed.

, The guide ribs 4 serve to guide the plug 1 into place with respect to the receptacle I- and the attachment of plug to the receptacle can be effected in the dark or where it is only possible to feel for the receptacle.

While I have illustrated in Figs. 1 to 3 what may be the preferred embodiment of my invention, it may assume many different forms, the most important of which I have illustrated and will describe.

In the form of the invention illustrated in Figs. 1 to 3, the guiding ribs 4 are on the face plate 5 whereas the cross-sloti of semi-circular crosssection which forms the bearing for the hook member 6 of' the plug 1 is on the boss 2 of the receptacle I. As illustrated in Figs. 4- vand 5 both guide ribs and cross-slot are formed on the face plate, the latter being constituted by turning up the metal of the face plate into a transverse trough ID of semi-circular cross-section, the receptacle I being of the usual orthodox construction.

In the modification illustrated in Figs. 6 to 8 the hook member on the plug 1 assumes the form of a radially extending lug ll having a transverse pin l2 extending therethrough and its ends protruding therefrom and constituting trunnions in- 'sertable into opposed trough-shaped members 13 secured to the face plate. Each trough shaped member is c-shape in horizontal section'with a space therebetween to receive the lug II when the hook member is applied to the trough-shaped members.

In the modification illustrated in Figs. 9 and 10 the receptacle l and the face plate 5 are of unitary construction such as would be the case were they cast from Bakelite or other similar material and the semi-circular cross-slot is formed on the receptacle portion, the face plate portion having an indentation l4 to receive the hook member of the plug. Such indentation may taper, if desired, from its open end to the junction with the cross-slot.

In order that I may use an orthodox plug with an outlet constructed according to my invention such as is illustrated in Figs. 1 to 3, Figs. 4 and 5, or Figs. 9 and 10, I may provide a split collar l5 having a hook member I6 thereon, and secure 5 such collar l5 around the periphery of the plug having a transverse slot or groove 20 therein to 1 receive the transverse hook ,member 6 on the plug 1, the plug being adapted to be swung into and out of its operative position with respect to the screw plug exactly as it would with respect to guiding ribs are necessary.

From the above description it will be apparent that I have devised a convenience outlet in which it is possible to guide the plug to the receptacle the receptacle I, except that in this instance no a as well as ensure that such plug is locked to the receptacle against accidental displacement. Moreover, due to the provision of the hook memher, the plug may only be non-reversedly attached to the receptacle and consequently where such outlet is used in a polarized direct current a circuit, the positive or negative contacts of the plug will always contact the corresponding contact of the receptacle.

What I claim as my invention is:

1. In an electrical convenience outlet, in coma bination', a plug having spaced apart tongue contacts and a hook shaped member extending outwardly from the periphery of the plug and including coaxially located trunnions on each side of its free end, the axes of the trunnions being perpendicular to the axis of the plug, a receptacle having spaced apart tongue contact receiving slots and contacts therein adapted tomake contact with the tongue contacts on the plug, and a pair of spaced apart ribs ofchannel cross-section located I at the front of the receptacle and respectively positioned at each end of a transverse trunnion receiving groove, said ribs constituting a guide way for slidably locating the trunnions in such groove whereby the plug is pivotally connected to the I.

receptacle and is adapted to be swung about such pivot point to insert the tongue contacts into the slots in the receptacle wherein they make contact with the contacts therein.

2. In an electrical convenience outlet, in comll 'bination, a plug having spaced apart tongue contacts and a hookshaped member extending outwardly from the periphery of the plug and including coaxially located trunnions on each side of its free end, the axes of the trunnions being perpendicular to the axis of the plug, a receptacle having spaced apart tongue contact receiving slots and contacts therein adapted to make contact with the tongue contacts on the plug, a pair of spaced apart ribs of channel cross-section located 66 at the front of the receptacle, a transversetrunnion receiving bearing of semi-circular crosssection located between the ends of the ribs adjacent to the tongue receiving slots for receiving the trunnions on the hook member of the plug 70 ating to lock the plug against displacement from the receptacle except when said plug is reversedly swung. I

3. In an electrical convenience outlet, in combination, a plug having spaced apart tongue contacts and a hook-shaped member extending outwardly from the periphery and including coaxially located trunnions on each side of its free end, the axes of the trunnions being perpendicular to the axis of the plug, a receptacle having spaced apart tongue contact receiving slots and contacts therein adapted to make contact with the tongue contacts on the plug, a transverse bearing of semi-circular cross-section on the face of the receptacle for receiving the trunnions whereby the plug is capable of being swung thereon into such position that its tongue contacts are inserted in the slots and make contact with the contacts therein, said trunnions and bearing cooperating to lock the plug against displacement from the receptacle except when said plug is reversedly swung, and a pair of spaced apart ribs located at the front of the receptacle and respectively positioned at each end of the bearing and perpendicular thereto adapted to engage the trunnions and guide them to the bearmg.

4. In an electrical convenience outlet, in combination, a plug having spaced apart tongue contacts and a hook-shaped member extending outwardly from the periphery and including coaxially located trunnions on each side of its free end, the axes of the trunnions being perpendicular to the axis of the plug, a receptacle having spaced apart tongue contact receiving slots and contacts therein adapted to make contact with the tongue contacts on the plug, a transverse bearing of semi-circular cross-section on the face of the receptacle for receiving the trunnions whereby the plug is capable of being swung thereon into such position that its tongue contacts are inserted in the slots andmake contact. with the contacts therein, said trunnions and bearing cooperating to lock the plug against displacement from the receptacle except when said plug is reversedly swung, and a pair of spaced apart ribs of channel cross-section located at the front of the receptacle and respectively positioned at each end of the bearing and perpendicular thereto adapted to engage the trunnions and guide them to the bearing, and preventing displacement of the plug from the receptacle until the trunnions are located in the bearings.

5. In an electrical convenience outlet, a plug having spaced apart tongue contacts and a hookshapedcmember including a cylindrical portion disposed substantially tangentially to the periphery oiflthe plug, a receptacle having spaced apart tongue contact receiving slots and contacts therein adapted to make contact with the tongue contacts on the plug, a transverse bearing of semicircular cross-section on the face of the receptacle for receiving the cylindrical portion of the hook-shaped member whereby the plug is capable of being swung thereon into such position that its tongue contacts are inserted in the slots and make contact with the contacts therein, said cylindrical portion and bearing cooperating to lock the plug against displacement from the receptacle except when the plug is reversedly swung, and a pair of spaced apart ribs located at the front of the receptacle and respectively positioned at each end of the bearing and perpendicular thereto adapted to engage the ends of the cylindrical portion of the hook-shaped member and guide it into the bearing.

- ROBERT W. HAGGAR, 

